Abstract
In security camera, the exposure control system, called Iris meter, is widely applied to provide the optimal aperture of the lens for brightness. Sometimes, the unexpected vibration of the exposure control system is observed when the lens aperture is in the transient state of opening and closing. Such the vibration may not only lead the system status to the abnormal condition, but also play an important role in the long-term reliability of the system. The purpose of this paper is to examine the vibration of the exposure control system in security camera. First, some experiments are conducted to observe the dynamic properties of the system at the normal and abnormal condition. Second, theoretical discussion is made to give some information on the excitation mechanism of the vibration.